Saguner et al reported that sustained monomorphic ventricular tachycardia induced during electrophysiologic (EP) study predicted adverse outcomes in 69 patients with arrhythmogenic right ventricular cardiomyopathy (ARVC). They concluded that an EP study has a role in risk stratification. They stated that 44 of the 62 patients had spontaneous sustained ventricular tachycardia (VT) before the EP study and were included in the analysis. One would assume that patients with clinical sustained VT will have inducible sustained VT or ventricular fibrillation (VF) during EP study. If so, what is the benefit of risk stratification by performing an EP study in patients with clinical sustained VT?

In a detailed report of EP studies on 34 patients with ARVC by Pezawas et al, 22 patients had clinical sustained VT. Of these, 19 had VT induced at EP study with ventricular rates that were similar to that during the clinical VT. Three patients with clinical VT were not inducible. They concluded: “In ARVD/C the tachycardia cycle length of clinical VT, programmed ventricular stimulation (PVS), induced VT and follow-up VT correlate well implicating that a PVS-guided approach does not provide additional information. Spontaneous arrhythmia in combination with clinical presentation allows identification of patients in need for an ICD.” It is clear that patients with clinical sustained VT are at risk for subsequent VT/VF and generally should be treated with an ICD. The question then arises as to the role of EP study for risk stratification in patients with ARVC who have clinical sustained VT or VF.